Between (fictional place)

Between in Anne McCaffrey's Dragonriders of Pern series is a dimension through which dragons, watch-whers and fire lizards travel during the process of teleportation, referred to as "going between". If the dragon does not have a clear picture of its destination in mind, it is possible for the dragon and its passengers to become permanently lost in this dimension. Deliberately going between without a destination in mind is how dragons commit suicide, usually occurring when the rider that they are soul-bonded with dies of illness or injury, or if the dragon itself is mortally injured. Many characters, fire lizards, and dragons have been lost between (i.e. " Moreta's Ride"). In Todd McCaffrey's Dragonsblood, several make it out of between after they are lost.

Between is universally described as a place of nothingness. Usually, for a dragon to teleport using its rider's directions, they stay in between for the time that it takes to cough three times. Fire lizards take eight seconds to teleport anywhere on the planet. Between frequently causes cystitis and child-bearing problems in female dragonriders. Going between without proper coordinates is a frequent cause of death for inexperienced weyrlings. Dragons generally excrete in between, except young dragons.

Between is characterized by extreme cold (far below zero yet not as cold as outer space) and induces near-total sensory deprivation in humans who travel through it on dragonback. There appears to be no breathable air between, and riders who make exceptionally long journeys suffer the effects of oxygen deprivation. In later books, an expedition on dragonback to the Red Star involved riders wearing spacesuits to alleviate this problem; dragons can hold their breath for much longer than humans without ill effects. Dragons and fire lizards deliberately go between to destroy any Thread which they come in contact with, as the extreme cold causes it to freeze almost instantly, whereupon it can be safely brushed off dragon or rider.

...
Wikipedia